The disclosure features immune cell delivery lipid nanoparticle (LNP) compositions that allow for enhanced delivery of agents, e.g., nucleic acids, such as therapeutic and/or prophylactic RNAs, to immune cells, in particular T cells, as well as B cells, dendritic cells and monocytes. The LNPs comprise an effective amount of an immune cell delivery potentiating lipid such that delivery of an agent by an immune cell delivery LNP is enhanced as compared to an LNP lacking the immune cell delivery potentiating agent. Methods of using the immune cell delivery LNPs for delivery of agents, e.g., nucleic acid delivery, for protein expression, for modulating immune cell activity and modulating immune responses are also disclosed.

Certain aspects of the present invention are directed to a method for making a protein blocking assembly reversibly linking a therapeutic protein to a blocking group via a linker moiety. Additional aspects of the invention are directed to the protein blocking assembly, and to methods of administering the protein blocking assembly to a subject, where the protein is cleaved from the protein blocking assembly.

Disclosed are a natural killer (NK) cell expressing an anti-cotinine chimeric antigen receptor (CAR) specifically binding to cotinine, and a cell therapeutic agent containing the NK cell. The CAR-expressing NK cell which specifically binds cotinine, can effectively move to tumor tissue, regardless of the kind of cancer, depending on the binding substance bound to cotinine. Therefore, the natural killer cell can be usefully employed as a gene therapy exhibiting a highly efficient anticancer effect.

Provided herein are methods and compositions useful for treating PDL1 and/or PDL2 positive cancers through adoptive cell transfer of T cells genetically engineered to express a PD1-specific chimeric antigen receptor. Co-stimulatory domains such as Dap 10 may be included to enhance efficacy.

The present invention generally embraces the treatment of diseases by targeting cells expressing an antigen on the cell surface. In particular the invention relates to recombinant antigen receptors and uses thereof. T cells engineered to express such antigen receptors are useful in the treatment of diseases characterized by expression of one or more antigens bound by the antigen receptors.

A method to expand hematopoietic stem and progenitor cells (HSPC) wherein the method comprises obtaining an isolated population of HSPC the culturing the isolated population of HSPC in the presence of a histone deacetylase inhibitor (HDAC inhibitor), to form a cultured population, then adding an aminothiol compound to the cultured population.

PD1-41BBL fusion proteins are provided. Accordingly, there is provided a PD1-41BBL fusion protein comprising a single amino acid linker between the PD1 and the 41BBL. Also there is provided a PD1-41BBL fusion protein, wherein the PD1 amino acid is 123-166 amino acids in length and/or wherein the PD1 amino acid sequence comprises SEQ ID NO: 2 and/or wherein the fusion protein is in a form of at least a homo-trimer. Also provided are polynucleotides and nucleic acid constructs encoding the PD1-41BBL fusion protein, host-cells expressing the PD1-41BBL fusion protein and methods of use thereof.

The present invention relates to novel regulatory T cell proteins. One protein, designated PD-L3, resembles members of the PD-L1 family, and co-stimulates αCD3 proliferation of T cells in vitro. A second, TNF-like, protein has also been identified as being upregulated upon αCD3/αGITR stimulation. This protein has been designated T.sup.reg-sTNF. Proteins, antibodies, activated T cells and methods for using the same are disclosed.

In particular methods of using these proteins and compounds, preferably antibodies, which bind or modulate (agonize or antagonize) the activity of these proteins, as immune modulators and for the treatment of cancer, autoimmune disease, allergy, infection and inflammatory conditions, e.g. multiple sclerosis is disclosed

Provided herein are immunomodulatory proteins comprising variant PD-L1 and nucleic acids encoding such proteins. The immunomodulatory proteins provide therapeutic utility for a variety of immunological and oncological conditions. Compositions and methods for making and using such proteins are provided.

The present disclosure relates extracellular vesicles, e.g., exosomes, comprising an antigen-binding moeity, e.g., a single-domain antigen-binding moeity, e.g., a vNAR, a VHH, or a fragment thereof, that specifically binds transferrin receptor, and methods of making and using the same.